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Yucca
|}} Yucca is a genus of perennial shrubs and trees in the agave family, Agavaceae. Its 40-50 species are notable for their rosettes of evergreen, tough, sword-shaped leaves and large terminal panicles of white or whitish flowers. They are native to the hot and dry (arid) parts of North America, Central America, South America, and the Caribbean. Early reports of the species were confused with the cassava (Manihot esculenta). Consequently, Linnaeus mistakenly derived the generic name from the Carib word for the latter, yuca. It is also colloquially known in the midwest United States as "Ghosts in the graveyard", as it is commonly found growing in rural graveyards and when in bloom the flowers appear as an apparition floating. Distribution The natural distribution range of the genus Yucca (49 species and 24 subspecies) covers a vast area of North and Central America. From Baja California in the west, northwards into the southwestern United States, through the drier central states as far north as Alberta in Canada (Yucca glauca ssp. albertana), and moving east along the Gulf of Mexico, and then north again, through the Atlantic coastal and inland neighbouring states. To the south, the genus is represented throughout Mexico and extends into Guatemala (Yucca guatemalensis). Yuccas have adapted to an equally vast range of climatic and ecological conditions. They are to be found in rocky deserts and badlands, in prairies and grassland, in mountainous regions, in light woodland, in coastal sands (Yucca filamentosa), and even in subtropical and semi-temperate zones, although these are generally arid to semi-arid. Ecology Yuccas have a very specialized, mutualistic pollination system, being pollinated by yucca moths (family Prodoxidae); the insect purposefully transfers the pollen from the stamens of one plant to the stigma of another, and at the same time lays an egg in the flower; the moth larva then feeds on some of the developing seeds, always leaving enough seed to perpetuate the species. Yucca species are the host plants for the caterpillars of the Yucca Giant-Skipper (Megathymus yuccae), Ursine Giant-Skipper (Megathymus ursus), and Strecker's Giant-Skipper (Megathymus streckeri). Uses Yuccas are widely grown as ornamental plants in gardens. Many species of yucca also bear edible parts, including fruits, seeds, flowers, flowering stems, and more rarely roots. References to yucca root as food often stem from confusion with the similarly spelled but botanically unrelated yuca, also called cassava (Manihot esculenta). Roots of soaptree yucca (Yucca elata) are high in saponins and are used as a shampoo in Native American rituals. Dried yucca leaves and trunk fibers have a low ignition temperature, making the plant desirable for use in starting fires via friction. Cultivation Yucca are widely planted in the western US as a landscape plant. Most species are generally heat and cold tolerant, requiring little care and low water. They offer a dramatic accent to a landscape design. Joshua trees (Yucca brevifolia) are protected by law in some states and should not be wild collected without permit. As a landscape plant, they can be killed by excessive water during their summer dormant phase. For these two reasons they are avoided by landscape contractors. Symbolism The "yucca flower" is the state flower of New Mexico. No species name is given in the citation. Species A number of other species previously classified in Yucca are now classified in the genera Dasylirion, Furcraea, Hesperaloe, Hesperoyucca and Nolina. Taxonomic arrangement *Section Yucca formerly Sarcocarpa Engelm. **Series Faxonianae Hochstätter ***''Yucca carnerosana'' (Trel.) McKelvey ***''Yucca faxoniana'' (Trel.) Sarg. **Series Baccatae Hochstätter ***''Yucca baccata'' Torr. ****''Yucca baccata'' Torr. ssp. baccata ****''Yucca baccata'' Torr. ssp. vespertina (McKelvey) Hochstätter ****''Yucca baccata'' Torr. ssp. thornberi (McKelvey) Hochstätter ***''Yucca confinis'' McKelvey ***''Yucca endlichiana'' Trel. ***''Yucca arizonica'' McKelvey **Series Treculianae Hochstätter ***''Yucca grandiflora'' Gentry ***''Yucca declinata'' Laferr. ***''Yucca treculiana'' Carriere ***''Yucca torreyi'' Shafer ***''Yucca schidgera'' Roezl ex Ortgies ***''Yucca schotti'' Engelm. ***''Yucca capensis'' Lenz ***''Yucca jaliscensis'' Trel. ***''Yucca periculosa'' Baker ***''Yucca mixtecana'' Garcia-Mend. ***''Yucca decipiens'' Trel. ***''Yucca valida'' Brandegee ***''Yucca potosina'' Rzed. ***''Yucca filifera'' Chabaud **Series Gloriosae Hochstätter ***''Yucca gloriosa'' L. ***''Yucca recurvifolia'' Salisb. **Series Yucca ***''Yucca madrensis'' Gentry ***''Yucca linearifolia'' Clary ***''Yucca elephantipes'' Regel ***''Yucca lacandonica'' Gomez-Pompa & Valdes ***''Yucca aloifolia'' L. ***''Yucca yucatana'' Engelm. *Section Clistocarpa Engelm. ***''Yucca brevifolia'' Engelm.) ****''Yucca brevifolia'' Engelm. ssp. brevifolia ****''Yucca brevifolia'' Engelm. ssp. jaegeriana (McKelvey) Hochstätter ****''Yucca brevifolia'' Engelm. ssp. herbertii (Webber) Hochstätter *Section Chaenocarpa Engelm. **Series Filamentosae Hochstätter ***''Yucca filamentosa'' L. ****''Yucca filamentosa'' L. ssp. filamentosa ****''Yucca filamentosa'' L. ssp. smalliana (Fernald) Hochstätter ****''Yucca filamentosa'' L. ssp. concava (Haw.) Hochstätter ***''Yucca flaccida'' Haw. **Series Rupicolae Hochstätter ***''Yucca cernua'' Keith ***''Yucca pallida'' McKelvey ***''Yucca queretaroensis'' Pina Lujan ***''Yucca reverchonii'' Trel. ***''Yucca rigida'' (Engelm.) Trel. ***''Yucca rostrata'' Engelm. ex Trel. ***''Yucca rupicola'' Scheele ***''Yucca thompsoniana'' Trel. **Series Harrimaniae Hochstätter ***''Yucca harrimaniae'' Trel. ****''Yucca harrimaniae'' Trel. ssp. harrimaniae ****''Yucca harrimaniae'' Trel. ssp. neomexicana (Wooton & Standl.) Hochstätter ****''Yucca harrimaniae'' Trel. ssp. sterilis (Neese & Welsh) Hochstätter ****''Yucca harrimaniae'' Trel. ssp. gilbertiana (Trel.) Hochstätter ***''Yucca nana'' Hochstätter **Series Glaucae (McKelvey) Hochstätter ***''Yucca angustissima'' Engelm. ex Trel. ****''Yucca angustissima'' Engelm. ex Trel. ssp. angustissima ****''Yucca angustissima'' Engelm. ex Trel. ssp. toftiae (Welsh) Hochstätter ****''Yucca angustissima'' Engelm. ex Trel. ssp. kanabensis (McKelvey) Hochstätter ****''Yucca angustissima'' Engelm. ex Trel. ssp. avia (Reveal) Hochstätter ***''Yucca baileyi'' Wooton & Standl. ****''Yucca baileyi'' Wooton & Standl. ssp. baileyi ****''Yucca baileyi'' Wooton & Standl. ssp. intermedia (McKelvey) Hochstätter ***''Yucca coahuilensis'' Matuda & Pinja Lujan ***''Yucca elata'' Engelm. ****''Yucca elata'' Engelm. ssp. elata ****''Yucca elata'' Engelm. ssp. utahensis (McKelvey) Hochstätter ****''Yucca elata'' Engelm. ssp. verdiensis (McKelvey) Hochstätter ***''Yucca glauca'' Nutt. ****''Yucca glauca'' Nutt. ssp. glauca ****''Yucca glauca'' Nutt. ssp. stricta (Sims) Hochstätter ****''Yucca glauca'' Nutt. ssp. albertana Hochstätter ***''Yucca campestris'' McKelvey ***''Yucca constricta'' Buckley ***''Yucca arkansana'' Trel. ****''Yucca arkansana'' Trel. ssp. arkansana ****''Yucca arkansana'' Trel. ssp. louisianensis (Trel.) Hochstätter ****''Yucca arkansana'' Trel. ssp. freemanni (Shinners) Hochstätter *Section Hesperoyucca Engelm. ***''Yucca whipplei'' Torr. ****''Yucca whipplei'' Torr. ssp. whipplei ****''Yucca whipplei'' Torr. ssp. caespitosa (Jones) Haines ****''Yucca whipplei'' Torr. ssp. intermedia Haines ****''Yucca whipplei'' Torr. ssp. percursa Haines ****''Yucca whipplei'' Torr. ssp. newberryi (McKelvey) Hochstätter ****''Yucca whipplei'' Torr. ssp. eremica Epling & Haines Cultivars In the years from 1897 to 1907, Carl Ludwig Sprenger created and named 122 Yucca hybrids. References Category:Yucca